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hvdc用直流滤波电容器组均压技术研究

电力电容器与无功补偿 2024年第4期45卷 1-5页

作者：左强林赵彦军孙振瑜无锡赛晶电力电容器有限公司江苏无锡214100 广西大学南宁530000

本文从hvdc用直流滤波电容器的台架结构出发,研究了台架设计对直流电压分配的影响,研究了电容器外壳连接元件串联段数、泄漏比与直流电压不均匀系数的关系,得出元件串联段数越多直流电压分配越不均匀的结论;结合电容器单元的特点,得出... 详细信息

本文从hvdc用直流滤波电容器的台架结构出发,研究了台架设计对直流电压分配的影响,研究了电容器外壳连接元件串联段数、泄漏比与直流电压不均匀系数的关系,得出元件串联段数越多直流电压分配越不均匀的结论;结合电容器单元的特点,得出电容器的电时间常数是一个仅与ρε相关的常数的结论,并依据上述结论分析了大容量直流电容器组运行不理想的原因,给出了直流滤波电容器组的设计建议。

关键词： hvdc 直流滤波电容器均压措施直流电压不均匀系数泄漏比电时间常数

AC fault ride through control strategy on inverter side of hybrid hvdc transmission systems

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1129-1141页

作者： Zexin ZHOU Zhengguang CHEN Xingguo WANG Dingxiang DU Guosheng YANG Yizhen WANG Liangliang HAO China Electric Science Research Institute Co. Ltd.BeijingChina State Key Laboratory for Power Grid Safety and Energy Conservation BeijingChina School of Electrical Engineering and Automation Tianjin UniversityTianjinChina College of Electrical Engineering Beijing Jiaotong UniversityBeijingChina

Hybrid high-voltage direct current(hvdc)transmission systems employ a new type of hvdc transmission topology that combines the advantages of the linecommutated converter system and the voltage-source converter *** can improve the efficiency and reliability of long-distance power ***,realizing alternating-current(AC)grid-fault ride through on the inverter side of a hybrid hvdc transmission system is a challenge considering that a voltage-source converter based hvdc(VSC-hvdc)is used on the inverter *** this study,a control strategy for an overvoltage fixed trigger angle based on the power-balance method is developed by fully utilizing the operation characteristics of a hybrid hvdc transmission *** strategy reduces the inverter-side overvoltage of the hvdc system under a fault in the inverter-side AC *** based on Gezhou Dam are conducted to validate the effectiveness of the proposed strategy.

关键词： Hybrid hvdc transmission Fault crossing Control strategy Inverter side

Novel Fast Operating Moving Coil Actuator with Compensation Coil for hvdc Circuit Breakers

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CSEE Journal of Power and Energy Systems 2021年第5期7卷 1041-1050页

作者： Boyuan Yin Xianwu Zeng John F.Eastham Damian Vilchis-Rodriguez Xiaoze Pei Department of Electronic&Electrical Engineering.University of Bath.Bath.United Kingdom Department of Mechanical Engineering University of Bath.Bath.United Kingdom. Power and Energy Division School of Electrical and Electronic EngineeringThe University of ManchesterManchester M139PLUnited Kingdom.

DC circuit breakers are major enabling components for multi-terminal hvdc *** key design targets are operating speed and *** paper proposes a novel moving coil actuator using a compensation coil topology to operate mechanical circuit *** topology aims to significantly improve the magnetic field saturation and reduce the system inductance,so that the operating speed is *** possible connection methods for the compensation coils are proposed and analyzed using finite element modeling,ensuing simulation results are compared and *** operating speed of the moving coil actuator with compensation coils is significantly improved compared with the original moving coil *** moving coil actuator with compensation coils can open a distance of 5 mm within 2.8 ms and the peak efficiency is 47%.

关键词： Compensation coil DC circuit breaker hvdc mechanical circuit breaker moving coil actuator

Sequential auto-reclosing strategy for hybrid hvdc breakers in VSC-based DC grids

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Journal of Modern Power Systems and Clean Energy 2019年第3期7卷 633-643页

作者： Xiangyu PEI Guangfu TANG Shengmei ZHANG China Electric Power Research Institute Beijing100192China Global Energy Interconnection Research Institute Co.Ltd. Beijing102209China North China Electric Power University Beijing102206China

The use of overhead lines for power transmission in the future high-voltage and large-capacity voltagesource converter(VSC)-based direct current(DC) grid will significantly increase the probability of temporary *** eliminate potential adverse impacts such as erroneous protection, line-insulation failure, and even damage to power electronic devices resulting from a DC breaker reclosing operation with the traditional sequential autoreclosing strategy, a new sequential auto-reclosing strat-egy for hybrid hvdc breakers(HHBs) in VSC-based DC grids is proposed. This strategy is based on the step-by-step operation of the transfer branch in the HHB. As a result,du/dt resulting from the HHB reclosing operation is greatly reduced, and therefore those potential negative impacts can be eliminated. Several other advantages are also *** feasibility and validity of the proposed strategy are verified in a four-terminal annular VSC-based DC grid electromagnetic transient model.

关键词： Overhead line Voltage-sourced converter(VSC)-based direct current grid Temporary fault Hybrid hvdc breaker(HHB) Auto-reclosing strategy

Study on influencing factors of ion current density measurement in corona discharge of hvdc transmission lines

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Plasma Science and Technology 2020年第4期22卷 1-7页

作者： Shiqiang LIU Shouzheng LI Yuze JIANG Nan JIANG Jie LI Yan WU School of Electrical Engineering Dalian University of TechnologyDalian 116024People's Republic of China State Grid Shandong Electric Power Research Institute Jinan 250003People's Republic of China

The ground level ion current density produced by corona discharge in high voltage direct current(hvdc)transmission lines can reflect the operation status of the lines,but the distorted electric field at the edge of the Wilson plate seriously affects the measurement results of ion current *** order to measure the ground level ion current density accurately and directly,a new reduced scale wire-plate experimental device in which the Wilson plate is flush with the grounding plate is *** influence of protective annulus width and the height of the Wilson plate from the grounding plate on ground level ion current density are *** addition,the differences between the micro-current galvanometer method and the sampling resistance method in the measurement of ion current density are ***,the ground level ion current density distributions of unipolar and bipolar hvdc transmission lines are *** results show that the edge effect of the Wilson plate can be neglected when the width of protective annulus is less than 2 mm,and the ion current density is nonlinear with the height of the Wilson plate from the grounding ***,the internal resistance of the digital voltmeter seriously affects the measurement results and it is necessary to correct the ***,at the same applied voltage,the ground level ion current density in the negative conductor region is higher than that in the positive conductor region.

关键词： hvdc corona discharge reduced scale device Wilson plate ion current density

Measurement of surface charges on the dielectric film based on field mills under the hvdc corona wire

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Plasma Science and Technology 2018年第5期20卷 51-60页

作者： Donglai WANG Tiebing LU Yuan WANG Bo CHEN Xuebao LI State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206People＇s Republic of China

The ion flow field on the ground is one of the significant parameters used to evaluate the electromagnetic environment of high voltage direct current（hvdc） power *** lines may cross the greenhouses due to the restricted transmission *** the condition of ion flow field,the dielectric films on the greenhouses will be charged,and the electric fields in the greenhouses may exceed the limit *** mills are widely used to measure the groundlevel direct current electric fields under the hvdc power *** this paper,the charge inversion method is applied to calculate the surface charges on the dielectric film according to the measured ground-level electric *** advantages of hiding the field mill probes in the ground are *** charge inversion algorithm is optimized in order to decrease the impact of measurement *** on the experimental results,the surface charge distribution on a piece of quadrate dielectric film under a hvdc corona wire is *** enhanced effect of dielectric film on ground-level electric field is obviously weakened with the increase of film *** with the total electric field strengths,the normal components of film-free electric fields at the corresponding film-placed positions have a higher effect on surface charge accumulation.

关键词： corona discharge dielectric film hvdc ion flow field surface charge accumulation

Dynamics and Small Signal Stability Analysis of PMSG-based Wind Farm with an MMC-hvdc System

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CSEE Journal of Power and Energy Systems 2020年第1期6卷 226-235页

作者： Yifan Wang Chengyong Zhao Chunyi Guo Atiq Ur Rehman The State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

The permanent magnet synchronous generator (PMSG)-based wind farm with a modular multilevel converter (MMC) based hvdc system exhibits various oscillations and can experience dynamic instability due to the interactions between different controllers of the wind farm and MMC stations, which have not been properly examined in the existing literatures. This paper presents a dynamic modeling approach for small signal stability analysis of PMSG-based wind farms with a MMC- hvdc system. The small signal model of the study system is validated by the comprehensive electromagnetic transient (EMT) simulations in PSCAD/EMTDC. Then the eigenvalue approach and participation factors analysis are utilized to comprehensively evaluate the impact of different controllers, system’s parameters and the circulating current suppressing controller (CCSC) on the small signal stability of the entire system. From eigenvalue analysis, it is revealed that as the output active power of the wind farm increases within the rated range, the overall system will exhibit a sub-synchronous oscillation (SSO) instability mode, an extremely weak damping mode, and a low frequency oscillation instability mode. From participation factors analysis, it is observed that the SSO mode and weak damping mode are primarily related to the internal dynamics of the MMC, which can be suppressed or improved by CCSC. It is determined that the low frequency oscillation mode is primarily caused by the interactions between the phase locked loop (PLL) control of the wind farm and the voltage and frequency (V-F) control of the MMC station. The analysis also depicts that the larger proportional gain value of the V-F control of the MMC station and smaller PLL bandwidth of the wind farm can enhance the small signal stability of the entire system.

关键词： hvdc modular multilevel converter(MMC) permanent magnet synchronous generator(PMSG) small signal stability sub-synchronous oscillation(SSO) wind farm

A comprehensive review of DC fault protection methods in hvdc transmission systems

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Protection and Control of Modern Power Systems 2021年第1期6卷 1-20页

作者： Mohan Muniappan Senior Research Specialist Center for Future Energy Systems(CFES)Rensselaer Polytechnic Institute(RPI)TroyNew YorkUSA

High voltage direct current (hvdc) transmission is an economical option for transmitting a large amount of power over long distances. Initially, hvdc was developed using thyristor-based current source converters (CSC). With the development of semiconductor devices, a voltage source converter (VSC)-based hvdc system was introduced, and has been widely applied to integrate large-scale renewables and network interconnection. However, the VSC-based hvdc system is vulnerable to DC faults and its protection becomes ever more important with the fast growth in number of installations. In this paper, detailed characteristics of DC faults in the VSC-hvdc system are presented. The DC fault current has a large peak and steady values within a few milliseconds and thus high-speed fault detection and isolation methods are required in an hvdc grid. Therefore, development of the protection scheme for a multi-terminal VSC-based hvdc system is challenging. Various methods have been developed and this paper presents a comprehensive review of the different techniques for DC fault detection, location and isolation in both CSC and VSC-based hvdc transmission systems in two-terminal and multi-terminal network configurations.

关键词： hvdc VSC Multi-terminal DC grid DC fault Fault detection and location Fault isolation

Surface Charging Phenomena on hvdc Spacers for Compressed SF_(6) Insulation and Charge Tailoring Strategies

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CSEE Journal of Power and Energy Systems 2020年第1期6卷 83-99页

作者： Chuanyang Li Yuan Xu Chuanjie Lin Geng Chen Youping Tu Yao Zhou Zhipeng Lei Tao Han Simone Vincenzo Suraci Jian Wang Weidong Liu M.Tariq Nazir Shun He Andrea Cavallini Giovanni Mazzanti Davide Fabiani Jinliang He Electrical Insulation Research Center Institute of Materials ScienceElectrical and Computer EngineeringUniversity of ConnecticutStorrsCT 06269USA. China Electric Power Research Institute Beijing 100192China Department of Electrical Electronicand Information Engineering“Guglielmo Marconi”University of BolognaViale Risorgimento 2Bologna40136Italy State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Beijing Area Major Laboratory of High Voltage and Electromagnetic Compatibility North China Electric Power UniversityBeijing 102206China Shanxi Key Laboratory of Mining Electrical Equipment and Intelligent Control National and Provincial Joint EngineeringTaiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Smart Grid of Education Ministry School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China School of Mechanical and Manufacturing Engineering University of New South Wales SydneyNSW 2052Australia Electric Power Research Institute Yunnan Electric Power Grid Co.ltd.KunmingYunnan 650217China

Surface flashover of spacers is a key factor limiting the application of hvdc GIS/GIL,while the charge accumula-tion on the surface of the spacer could have a potential adverse effect on the surface flashover *** paper discusses the laws regarding distribution patterns of surface charges and the related *** field-dependent property is discussed in detail to comprehensively illustrate the charge transport mecha-nism and explain the research differences regarding different surface charge patterns obtained by previous *** addition,the main surface charge control methods for epoxy resin are summarized and *** potential research directions of charge control methods and key points in manufacturing of spacers used in hvdc GIS/GIL are also explored.

关键词： GIL hvdc insulator SF6 surface charge accumulation surface flashover